1. Field of the Invention
The present invention relates to an apparatus for catching an object, having a body to which a cylindrical tube open at both ends thereof, inflatable when supplied with a fluid such as air fixed at both ends thereof as sealed, whereby the fluid-filled object is caught by the surface of the tube inflated as the fluid is supplied into a sealed space defined between the tube and the body.
2. Description of the Prior Art
A typical conventional catching apparatus shown in FIG. 1 comprises a hollow cylindrical body 100, a flange 101 formed on the outer circumference of the body 100, an air passage 102 formed in the body and flange 101, a cylindrical tube 1 open at both ends thereof, inflatable when air is supplied and of which both ends are secured as sealed with calking rings 2 and 3, respectively, to the body 100, and a container 103 which is sealingly fixed to the flange 101. When a liquid L is supplied into an object 10 to be caught by this apparatus for the purpose of washing, the surface of contact between the tube 1 and the object 10 has to be sealed as the case may be.
Assume in this case that the pressure of the air A to be supplied into the tube 1 is P.sub.A and the pressure of the liquid L is P.sub.L. When the pressures are so adjusted that P.sub.A is smaller than P.sub.L, the liquid L in the container 103 will not leak out.
The object 10 shown in FIG. 1 has a sufficiently long portion thereof which is to be caught by the tube 1; however, in case of an object of which such portion is short, for example, in case blood filters 200 for artificial dialysis are held by a multi-head catching apparatus inside a dryer as shown in FIGS. 2 and 3, the air-supply tubes 200A are so short in some cases that when the dry air A.sub.1 is supplied into the filters 200, the air leaks out. If the pressure of the air A to be supplied into the tube 1 is raised for the purpose of preventing such air leak as well as for secure catching of the object 11, the tube 1 will close the opening of the object 11 as shown in FIG. 4, making it impossible to supply the liquid L (or the dry air A.sub.1) into the object 11. On the contrary, if the pressure of the air A is reduced, the sealing becomes poor as shown in FIG. 5, resulting in leak-out of the liquid L. Note that even in case it is not necessary to supply the liquid L into the object, if the portion of the object to be caught by the catching apparatus is smaller than the tube, the object cannot positively be caught.
In another typical conventional catching apparatus shown in FIGS. 6 to 9, the tube is inflated outwardly and the inflated surface of the tube 1' is partially used to retain the object 12 which is to be inspected using a probe 300. Such conventional catching apparatus is not advantageous in that when the tube 1' is inflated, a large distortion is likely to occur at a point T on the inflated surface opposite to the surface which touches the object 12, resulting in a puncture of the tube 1' along the line D starting at the point T. When the tube 1' is freely inflated, it will expand as shown in the left illustration of FIG. 10, but when the object 10 is pressed, the tube diameter at the point T becomes larger by d as shown in the right illustration of FIG. 10 and also the distortion exceeds the allowable value.